I have .454s in a FA, Ruger SuperRed, and Taurus Raging Bull. All are fine guns, but the FA is "finer".
You might want to rethink your scope choice. The .454 can be a long range round (150-200), but a 2Xcope is not a long range scope. Might want to consider a 2-8 Weaver or Leupold, 2-6 Simmons, or a Bushnell Elite 2-6 (not made, but pop up at times on some sites).
And for bullets, I never had luck with the XTPs. Recovered many from deer, especially on angled shots. A .454 has enough power to penetrate completely with the right bullet. I've taken 75+ deer with a 260 Speer HP, 250 Win. HP, 250 gr. Keith SWCs. All had 100% penetration on any angled shot.
The lighter bullets shoot flatter with more terminal damage than the heavies.
My FA .454 is my 100% turkey gun. I use the old Speer 260 gr. Mag HPs & a Bushnell 2-6X Elite. Hit them in the wing butt with no meat loss. Longest turkey shot is 129 yds. That gun has taken 37 turkeys without a loss.
I use SSKs T'SOB base. No problems in 20+ years.